Researchers have raised the alarm of possible dental risks associated with COVID-19. Other researchers have established that viruses can infect cells in the oral mucosa. The oral mucosa is the membrane lining the mouth. SARS-CoV-2 infects a cell by binding to the ACE2 (angiotensin-converting enzyme II) receptor.
The authors looked at how much ACE2 lined different human organs. They used the GTEx portal.
The researchers found that there is a higher concentration of the ACE2 receptor in salivary glands than the lungs. This means that the novel coronavirus can likely infect the salivary glands. Moreover, viral RNA of SARS-CoV can be detected before lung lesions occur. Thus, asymptomatic transmission of COVID-19 may occur from saliva, which can contain live virus. The researchers warn that infection of the salivary glands and not just infected saliva may cause asymptomatic infections.